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Old Nov 10, 2008, 8:17 AM   #1
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Hi Guys!

I am absolutely new in this field and am planning to buy a Canon XSi 450D. With this camera, I am getting a 18-55MM Lens in the kit. I just wanted to know what actually does this 18-55 MM means and more importantly, weather or not this lens has any zoom and if yes, how much.

Thank you.
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Old Nov 10, 2008, 8:23 AM   #2
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Yes it is a zoom. Those numbers, 18-55 tell you how much. Those numbers represent a PHYSICAL focal length. They need to be multiplied by 1.6 to get 'equivelent focal length'.

I'm guessing by your question you're looking for an answer like 3x, 4x, 8x, 10x etc...

That's a very misleading number and not very useful in the DSLR world. That number is simply max focal length / min focal length. The reason it's not very useful in the DSLR world is because zoom lenses there don't all start at 28-35mm as they typically do in the point-and-shoot world. A 100-300mm and 24-70 are both 3x lenses. But VERY different
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Old Nov 10, 2008, 9:08 AM   #3
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The Canon 18-55mm lens that comes with the 450D is a fine lens, one of the better kit lenses.It zooms from an angle of view fo about 65° to about 24°. That range covers most applications (family gatherings, sightseeing, etc.), but if you want to do sports or wildlife photos, you might want to get a longer lens. And if you want to do landscapes or architecture, you might want a wider lens.

What some people don't understand when they make the transition from P&S digicams to dSLRs is that, in dSLRs, the image sensor has a greater area, so the lens must have a greater area as well. This makes a dSLR lens considerably heavier. Also, dSLRs have mirrors that must flip up out of the way to take a photo, so the lens design is more complicated, which also makes it bigger and heavier. So making a lens for a dSLR that has the zoom range of lenses in P&S digicams, is difficult and expensive. So it's easier and cheaper to make lenses for dSLRsthat are more speciallized. The Canon 18-55 kit lens is a good, general purpose lens, and if you've got general purpose photography in mind, the kit lens is a good one to get. But if you are buying a dSLR exclusively to shoot sporting events, you can forget about the kit lens and get a lens that is more appropriate for that.

So, the fact that no one dSLRlens can do everything well is an advantage for dSLRs. You get to customize your camera for what you want to do, knowing that it will do it much better than any P&S digicam could do it.
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Old Nov 16, 2008, 6:42 AM   #4
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Hi folks, another newbie here.

Itoo am planning to purchase a 450D, and i have a question regarding the digital lenses.

When i take a photo of a garden bird with my Olympus 35mm camera and a 400mm lense, it fills the frame. What digital lense would do the same with the 450D?

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Old Nov 16, 2008, 6:48 AM   #5
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400mm on a 35mm film camera would be equivelent to a 250mm lens on a canon non 1-series DSLR. Those non 1 series Canon DSLRs have a sensor smaller than 35mm film so there is a 'crop factor' of 1.6. 400mm divided by 1.6 = 250mm.
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